A concise but strong review of the literature on bilinguals’ perception of ‘self’ led to the question of whether bilinguals perceive themselves as different or the same people when they function in different languages. 183 participants (N =183) randomly assigned to two half-groups took both the English and Persian versions of the Self Concept Scale (SCS) in two counter-balanced administration sessions with a time interval of 3 weeks. Results after analysis of the data using descriptive and inferential statistics indicated that Iranian-Americans have a more realistic self concept when they function in English than when they function in Persian. Their self concepts in English and Persian do not match. Moreover, the female Iranian-American shows a larger discrepancy in her English and Persian self concepts than her male counterpart. This indicates that females are more open to alienation than males are. The results of this study lend empirical support to claims made by previous researchers that bilinguals have a kind of split personality. It was concluded that a bilingual is not a unique person who assumes different identities when he functions in the different languages he knows, but that the bilingual possess two different guises or selves which are language-specific and are used in accordance with the language the bilingual speaks at any given point in time.